Task: Promote deployment artifacts completion into canonical memory

Identity

Promote the completion of task 20260814-go-deploy-artifacts-2a5f8e1d into canonical memory: record the commit, update the current-focus/next-steps narrative, mark the deployment-artifacts commitment completed, and append the recent tasks to integrated history.

Keep the "image build/push and target-cluster dry-run validation remain" boundary explicit; no production validation is claimed.
Only canonical documents and the integration task's own record change.

Added 4a8f2d5 to Integrated Through and the artifacts task to Recently Completed in current-state.md; the first Next step now reads "build and push the image, then dry-run validate manifests on the cluster".
Updated system-overview.md current-architecture paragraph: artifacts are checked in (backend/Dockerfile, deploy/ack/go-api.yaml, split Ingress); image build/push and cluster validation remain.
Marked the deployment-artifacts commitment Completed in commitments.md with the remaining build/push and validation next action.
Appended 20260814-deploy-model-reconcile-9b4c2e7f, 20260814-go-bootstrap-admin-6e2b7d9c, and 20260814-go-deploy-artifacts-2a5f8e1d to task-history.md.

check_doc_drift.py --task-id 20260814-deploy-artifacts-memory-5e1c3b8a passes.
npm run deploy:check unaffected (no manifest changes in this task).

Build and push the zhinian-go-api image and run kubectl apply --dry-run=server on the target cluster (tracked in commitments.md).
Decide whether to delete the deprecated worker.yaml and migration-job.yaml.